Circle the aardvarks in the back of the pickup trucks
Don't circle Otto von Bismarck
If you see orange spheres or purple-ish hearts, it's ok to circle those too.
Once you get to level 5, you lose lives for aardvarks that time out before being circled. (I've personally never gotten past level 5 yet, but I've gotten down to 1 second, so I know it's possible!)
left-click and hold to draw.
don't release until a complete circle has been made
space-bar to toggle drawing (so your finger doesn't get tired of click-holding)
right-click to pause
If
anybody knows how to bring up the onscreen keyboard so people can type
their names for high-scores on phones and tablets (on the HTML
platform), I'd love to know.

Any other suggestions are also welcome.

The music is from a band called "Locate the Source", which existed in
2010, and had exactly one album. You can listen to their
album for free on myspace.https://myspace.com/locatethesource/music/songs
The songs used in Circle the Aardvark in the Back of the Pickup Truck were "Some People" and "Cascade".

Also if anybody wants the source code, just ask, and maybe I'll post it to bitbucket. (six months later, nobody has asked, so I just posted it anyways... see it here)